Sleep Quality Calculator
Calculate your sleep quality score, total sleep time, and number of sleep cycles based on bedtime, wake time, and night interruptions.
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Total Sleep
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Sleep Cycles —
Quality Score —
How to Use This Calculator
- Enter your Bedtime (hour and minute in 24-hour format).
- Enter your Wake Time.
- Enter the number of Interruptions — times you woke up during the night.
- The calculator shows total sleep, sleep cycles, and a quality score out of 100.
Formula
Total Sleep = Wake Time − Bedtime (in hours)
Sleep Cycles = Total Sleep / 1.5
Quality Score = 100 − penalties for short sleep, interruptions, and late bedtime
Example
Bedtime 10:30 PM, wake 6:30 AM, 1 interruption.
- Total Sleep = 8 hours
- Sleep Cycles = 8 / 1.5 = 5.3 cycles
- Quality Score = 100 − 8 = 92/100
Frequently Asked Questions
- Most adults need 7–9 hours of sleep per night. Consistently sleeping less than 6 hours is linked to health risks including cardiovascular disease, obesity, and impaired cognition.
- A sleep cycle lasts approximately 90 minutes and includes light sleep, deep sleep, and REM sleep. A full night's sleep typically includes 4–6 complete cycles.
- Each awakening disrupts the sleep cycle, preventing you from completing full cycles of restorative deep sleep and REM sleep. Even brief awakenings reduce overall sleep quality.
- Sleep quality is best when aligned with your natural circadian rhythm. For most adults, this means sleeping between 10 PM and midnight and waking between 6–8 AM.